The broad objective of this research effort is to develop an empirically-based understanding of the natural history of drinking among Puerto Rican men in relation to a set of explanatory variables. The proposed research is an extension to another population segment (adult men) of our current research on adolescents to close the gaps in our understanding of alcohol use and abuse among Puerto Ricans. Based on our own research findings and those of other researchers, Puerto Ricans appear to exhibit a distinctive patterning by age in alcohol consumption and consumption-related consequences, a patterning that puts Puerto Rican men at greater risk than the general U.S. male population for the development of an array of health and social problems. This patterning has two features that are of direct research concern for the proposed effort: 1) a post-adolescence period of transition from rates of alcohol consumption and associated negative consequences lower than non-Hispanics to rates higher than non-Hispanics; and 2) a prolongation of heavy and abusive drinking to an age beyond that common among non-Hispanic men. Using a cross-sectional design based on an age-stratified sample of 500 Puerto Rican men and a community sampling procedure for structured interviewing, this research seeks to determine the dominant features of Puerto Rican adult male drinking behavior by examining: quantity/frequency of consumption, contexts of consumption, experimental effects of consumption, health and social consequences, attitudes toward drinking, individual and family drinking histories, and beverage preferences. The research also aims to determine the association between drinking behavior, onset of heavy and abusive drinking, and prolongation of heavy and abuse drinking and a set of socio-demographic, cultural, environmental, economic, and family history explanatory variables.